The conventional snowmobile has a rearwardly disposed drive belt and a forward steering assembly, the steering assembly comprising a pair of laterally spaced runners or skis. Skis for this purpose have generally been flat over a majority of their length, with downwardly projecting central longitudinal keels, and with upturned front tips to maintain the skis at the surface of the snow as they move forward. When it is desired to turn the vehicle, the two skis are manually rotated as a unit about a vertical axis, and the turning force on the vehicle is essentially that exerted by the snow on the downwardly depending keels of the skis. For optimum support or "floatation" on soft snow, it is desirable that the skis be relatively wide, but wider skis also limit the maneuverability and speed of the vehicle in that they tend to exert a greater drag or snow plowing effect. Wide skis also are less desirable from a maneuverability standpoint on hard-packed snow.
It is also well known that when traveling at high speeds on soft snow, the tips of the skis project powdery snow upward causing it to fly in the face of the vehicle driver and limit his visibility.